package com.yun;

public class Test1 {
    public static void main(String[] args) {
        User u = new User();
        u.i = new Integer(4);
        Test1 test1 = new Test1();
        System.out.println(u);
        test1.f1(u,u.i);
        System.out.println(u);
        System.out.println(u.i);
    }
    public void f1(User u,Integer i){
        //u.i = new Integer(5);
        //i = new Integer(5);
        //u = new User();
        u.setI(5);
        System.out.println(u);
    }
}

class User{
    Integer i;
    User(){}
    User(int i){
        this.i = i;
    }

    public void setI(Integer i) {
        this.i = i;
    }
}